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A087432
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Expansion of (1-3x+2x^2)/((1+x)(1-2x)(1-3x)).
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2
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1, 1, 3, 7, 19, 51, 143, 407, 1179, 3451, 10183, 30207, 89939, 268451, 802623, 2402407, 7196299, 21567051, 64657463, 193885007, 581480259, 1744091251, 5231574703, 15693326007, 47077181819, 141225953051, 423666674343
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| Binomial transform of A047849 (with interpolated zeros). Binomial transform is A087433.
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FORMULA
| a(n)=(-1)^n/6+0^n/3+2^n/3+3^n/6
For n>4, a(n) = 6*a(n-1) - 9*a(n-2) - 4*a(n-3) + 12*a(n-4). E.g. a(7) = 407 = 6*143 - 9*51 - 4*19 + 12* 7. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jun 14 2006
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CROSSREFS
| First differences of A093379.
Sequence in context: A026325 A002426 A011769 * A135052 A198305 A146597
Adjacent sequences: A087429 A087430 A087431 * A087433 A087434 A087435
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KEYWORD
| nonn
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Sep 02 2003
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